He devoted much attention to the study of the Jewish calendar.

Today was the second anniversary according to the Jewish calendar.

The Jewish calendar, is a lunar system with months of 29 or 30 days.

And then there is the disadvantage of operating under the Jewish calendar.

In fact the Jewish calendar has a multiplicity of new years for different purposes.

But he said that it was not unusual for such incidents to occur during special days on the Jewish calendar.

The Jewish calendar, of course, begins a new year this weekend.

These holidays occur on the same day of the year each year in the Jewish calendar.

There was no problem leaving the Jewish calendar unchanged.

He was notable for involving himself with perfecting the Jewish calendar in 359.